Partition sheet



A. M. MARTIN PARTITION SHEET July 7, 1931.

Filed Nov. 12, 1929 Patented July 7, 1931 PATENT OFFICE ALFRED M. MARTIN, OF CHICAGO, ILLINOIS PARTITION SHEET Application filed November 12, 1929. Serial No. 406,589.

These improvements relate to what are known as partition sheets or division sheets for loose-leaf binders.

My Patent No. 1,269,479 of June 11, 1918,

on Loose-leaf binders shows a type of looseleaf binderwith which thepresent partition sheetis peculiarly advantageous. In that patent Figs. 8 and 9 illustrate a form of r partition sheets described therein as an indeXed leaf for separating the account leaves. The account leaves refer-red to in said patent are the sheets or cards on which the thus forming a series of such cards from top to bottom of the binder. Such overlapping of the cards causes the thickness of the series to build up gradually in the direction in which the cards or sheets are applied, reaching its maximum .where there is a maximum ofsuch cards overlapping each other, the

thickness then diminishing toward the opposite end of the series Ordinarily the greatest thickness of the series develops in the central portion, measuring from top to bottom.

A single binder may contain a large number of such series of overlapped sheets, say

twenty-five or more. With the ordinary flat division or partition sheets between these respective series the book or binder device may be filled solidly throughout the middle portion thereof while at the top and bottom Y portions there is considerable free space between the covers. This arises from the fact that at the very top and at the very bottom of the device there may be only say twentyfive of the cards between the two outer covers, while at the same time there may be inthe middle two hundred and fifty or more of such cards between the opposed covers.

" My Patent No. 1,663,017 of March 20, 1928,

entitled Partition sheets for loose-leaf de- Vices illustrates, describes and claims another form of partltion sheet 1n which the eifective thickenmg of the upper and lower portions of the sheets is accomplished by embossing in various ways sheet-material of uniform thickness.

My copending application Serial No.

365,853, filed May 25, 1929, on Partition sheets for binders shows an integral device having continuous upper and lower surfaces and in which the character of the material used permits ofsuch an advantageous construction.

The main object of the present improve ments, like that of the device of Figs. 8 and 9 of my first-mentioned patent and that of the other devices referred to, is to provide a division or partition sheet for such uses which will occupy space between adjacent series of the overlapped cars, preferably at both the top and bottom portions of the overlapping series, whereby each series will be maintained more nearly flat when the book is opened and therefore be more free of the upwardly bulging effect of the middle portion of the series with certain advantages in practice such as a more free movement of the cards on the binder prongs, the cards being relieved of a certain objectionable bindthe maintenance of such a fiat surface at the top of the series is of particular advantage in the act of writing on the upper cards since otherwise this upper portion of the series would slope downward and away from the writer. Such a slope may be to quite a great extent; for instance there may be a difference of more than an inch and a half between the thickness at the middle and at the ends in a binder designed for two-inch capacity.

The more specific object of the present improvements is to provide adivision or partition sheet having a notable degree of strength and serviceability, coupled with the desired lightness and flexibility, while overcoming also the objections of outstanding parts against or under which the sheets'in the binder may become caught. 7

The present invention is characterized in general by continuous opposed surfaces, preterably throughout the unit, and especially over and under the thickened areas of the end portions of the sheet, Withthese'areas established by a plurality of pads or thickening ele} The partition Sh a 10 drug. 1 as an upperedge 11,a lower edge 12, an inneredge '13,'a I'1d an outer edge 14 defining a substantiallyrectangul'ar shape for the sheet in face "View. 'So'i'neti'mesthe corners of such sheets are rounded. Alongthe edge 13 is a row of .perforations15 adapted to receivethebinder prongs and constituting means for holding the sheet'in the binder. It is to be underleaves on which the records are kept are similarly p-unchedwith holes'to receive the iinpalingiprongs. j; V

As shown byFig.-2 the middle portion 16 or the sheet is fiat, 0t substantially uniform th ckness, and is relatively thin. This portion 16 may have the thicknessof ordinary ip'artition sheets. From this middle portion "16 th'eupper portion'17 and the lower portion 18 gradually increase in thickness toward the top and bottomedges" 11 and 12 respectively jwhere'by thesheetis substantially thickat or approximately edges. g 7

My improved partition sheet preferably inat these upper and lower other. Between sheets proper A andlB are a-iplurality of thickening pads 21, 22,- 23, 24

and 25 at the lower or bottom portion,' and 26,

27 28, 29 and :30 at the top or up-penpo rtion o f-the sheet. The stippling on the pads 21, :245 and 25-indicates-adhesive,'such as glue,

and alljof theseipads, are to be consideredas being. secured tov both of the sh'eets jproper A and B. The pads are spaced apart, andpreferably they form a-series extending betweentheside edges at each' end portion of the sheet" with the spaces between adjacent f pa'ds directed substantially parallel with the side edges 1'3'and 14:. The. spacing between pads 21' and 22 isgreater than that between other adjacent pads to fprovideigreater fl'eXi no is notstrictly essential.

where, in practice, the sheet is frequently flexed on shorter radii than elsewhere.

The stippling at 31 and 32 shows that along their side edges the sheets proper are secured together. It is quite advantageous to have them so secured, at least at 32, for this gives the device a unitary and strong edge atthe placewhere it ischiefly'han'dl'ed. Such gluing at 31 also strengthens the'device at h theholes 15 for-'the-binder prongs, but the gluing at 31 could be oinitted without substantial disadvantage, and the gluing at 32 Preferably-n0 gluingis done between the sheets proper in the central, part 16, and preferably thespaflces as '33, '34,"i35etc. between adjacent pads are likewiseleft'freeof glue. The construction shown provides all the desired flexibility.

It 1nay"be"pointed out that when the device asa whole isflexed, as-by abending movement which carries edge 14 toward "edge 15, the spacebetween the pads permits thei-n- "side'one of'the sheets pro-per togbuckle or bend inward at these spaces, thus providing for the necessary shortening of theinner ply. where the two plies A'and B are substantially v 'jwidely spaced apart. stoodthat the cards, sheets ,-:c

Gluing the sheets proper together between the adj acent pads. would permit of flexing 595 the sheet in practice, but it would resultin an uneven surface for one or both ofthesheets pro-per A and B, and I wish to "avoid all such f projections as would catch the sheets when j manipulated in the book. I- may point out-1n this connection that such gluingbetweenad- 'jacent pads might be-done at places where the record sheetsor account 'leaves would not ordinarily "c atclrinto the recesses thus, formed, andiatj suchp'laces the covering sheet,

as A, might-be discontinuous. The most satis- 1' factory results are obtained, however, according to the structure'in general of Figsul V and '2. 1 i cludes two sheets proper Aan'd B which are r opposed. to each other or in 'face-to-fa'ce relationandare preferably coextensive with each many uses any abruptnessof the. termination of such a thickener as 35 at its edge facing the :HllClCllQ portion would not "be objectionable. I 4.1

"In Figstthe sheets proper G terminateat '38 on thefull size sheet-proper D,and the pads 39' are in accordance with those-sho'wn-in in Figs. 5'the pads 40 show-theonly strucizri tural' difference over Fig. -1-eXcept -also for the stepped-effect given the sheet pr'oper'E, .the'sheet proper F preferably remaining fiat. Fig. 8 shows the pad'ofFigyfiii asbeing made,

of "laininations -of paper 'or" the like. Such pads are disclosed in my firstly-herein men tioned patent.

While the construction preferably includes both ends of the device thickened, one could use the device with but one end so enlarged, as by alternating these thickened ends in the book. I therefore do not wish to be limited to a double-ended device as shown.

.The pads of Fig. 6 and 7 may be made of cardboard, leather, wood, felt, etc. and those of Fig. 8 of relatively thin cardboard, heavy paper, etc. The sheets proper are preferably of a good strong and tough quality of paper, and Where we have two thicknesses of the material each thereof may be thinner than would ordinarily be used for a single partition sheet. Sheet D of Fig. 4 would be of the ordinary thickness.

I contemplate as being included in these improvements all such changes, departures and variations from what is thus specifically illustrated and described as fall within the scope of the appended claims.

' I claim:

1. For a loose-leaf binder of the character described, a partition sheet having an inner side edge, an outer side edge, and top and bottom edges, said edges defining a substantially rectangular shape and the sheet having upper and lower portions adjacent to said top and bottom edges respectively, with means adjacent to the inner edge of the sheet for holding it in the binder, said sheet comprising a sheet proper, a plurality of thickening pads spaced apart and positioned in one of said portions, a second sheet proper substantially coextensive with the first-mentioned sheet proper, facing the first mentioned sheet proper, and covering said pads and the areas between. the adjacent pads, with the pads secured to at least one of the-sheets proper.

2. The device of claim 1 hereof in which said sheets proper are free of attachment to each other throughout the middle portion of the device. 7

3. The device of claim 1 hereof in which the sheets properare secured to each other along the middle part of a marginal side edge thereof.

4. For a loose-leaf binder of the character described, a partition sheet having an inner sideedge, an outer side edge, and top and bottom edges, said edges defining a substantially rectangular shape and the sheet having upper and lower portions adjacent to said top and bottom edges respectively, with means adjacent tothe inner edge of the sheet for holding it in the binder, said sheet comprising a sheet proper, a plurality of thickening pads spaced apart and positioned in one of said portions, a second sheet proper facing the first-mentioned sheet proper and cov-,

V ering'said pads and the areas between the 1 adjacent pads, with the pads secured to at least one of the sheets proper, the sheets proper being secured along the middle part of a marginal side edge thereof.

5. The device of claim 1 hereof in which both the upper and lower portions of the sheet have the pad and sheet-proper construction specified in claim 1.

ALFRED M. MARTIN. 

